firecfg: turn constant strings into constants

Instead of using asprintf + free.

Also, use LIBDIR instead of hardcoded "/usr/lib" for fzenity.

Author: kmk3

src/firecfg/firecfg.h

@@ -37,6 +37,11 @@
 #include "../include/common.h"
 #define MAX_BUF 4096
 
+#define FIRECFG_CFGFILE SYSCONFDIR "/firecfg.config"
+#define FIREJAIL_EXEC PREFIX "/bin/firejail"
+#define FIREJAIL_WELCOME_SH LIBDIR "/firejail/firejail-welcome.sh"
+#define FZENITY_EXEC        LIBDIR "/firejail/fzenity"
+#define ZENITY_EXEC "/usr/bin/zenity"
 
 // main.c
 extern int arg_debug;

src/firecfg/main.c

@@ -76,10 +76,6 @@ static void list(void) {
 		exit(1);
 	}
 
-	char *firejail_exec;
-	if (asprintf(&firejail_exec, "%s/bin/firejail", PREFIX) == -1)
-		errExit("asprintf");
-
 	struct dirent *entry;
 	while ((entry = readdir(dir)) != NULL) {
 		if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0)
@@ -92,7 +88,7 @@ static void list(void) {
 		if (is_link(fullname)) {
 			char* fname = realpath(fullname, NULL);
 			if (fname) {
-				if (strcmp(fname, firejail_exec) == 0)
+				if (strcmp(fname, FIREJAIL_EXEC) == 0)
 					printf("%s\n", fullname);
 				free(fname);
 			}
@@ -101,7 +97,6 @@ static void list(void) {
 	}
 
 	closedir(dir);
-	free(firejail_exec);
 }
 
 static void clean(void) {
@@ -114,10 +109,6 @@ static void clean(void) {
 		exit(1);
 	}
 
-	char *firejail_exec;
-	if (asprintf(&firejail_exec, "%s/bin/firejail", PREFIX) == -1)
-		errExit("asprintf");
-
 	struct dirent *entry;
 	while ((entry = readdir(dir)) != NULL) {
 		if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0)
@@ -130,7 +121,7 @@ static void clean(void) {
 		if (is_link(fullname)) {
 			char* fname = realpath(fullname, NULL);
 			if (fname) {
-				if (strcmp(fname, firejail_exec) == 0) {
+				if (strcmp(fname, FIREJAIL_EXEC) == 0) {
 					char *ptr = strrchr(fullname, '/');
 					assert(ptr);
 					ptr++;
@@ -147,7 +138,6 @@ static void clean(void) {
 	}
 
 	closedir(dir);
-	free(firejail_exec);
 	printf("\n");
 }
 
@@ -175,24 +165,16 @@ static void set_file(const char *name, const char *firejail_exec) {
 	free(fname);
 }
 
-// parse /etc/firejail/firecfg.config file
-static void set_links_firecfg(void) {
-	char *cfgfile;
-	if (asprintf(&cfgfile, "%s/firecfg.config", SYSCONFDIR) == -1)
-		errExit("asprintf");
-
-	char *firejail_exec;
-	if (asprintf(&firejail_exec, "%s/bin/firejail", PREFIX) == -1)
-		errExit("asprintf");
+// parse a single config file
+static void set_links_firecfg(const char *cfgfile) {
+	printf("Configuring symlinks in %s based on %s\n", arg_bindir, cfgfile);
 
-	// parse /etc/firejail/firecfg.config file
 	FILE *fp = fopen(cfgfile, "r");
 	if (!fp) {
 		perror("fopen");
 		fprintf(stderr, "Error: cannot open %s\n", cfgfile);
 		exit(1);
 	}
-	printf("Configuring symlinks in %s based on firecfg.config\n", arg_bindir);
 
 	char buf[MAX_BUF];
 	int lineno = 0;
@@ -223,12 +205,10 @@ static void set_links_firecfg(void) {
 			continue;
 
 		// set link
-		set_file(start, firejail_exec);
+		set_file(start, FIREJAIL_EXEC);
 	}
 
 	fclose(fp);
-	free(cfgfile);
-	free(firejail_exec);
 }
 
 // parse ~/.config/firejail/ directory
@@ -245,10 +225,6 @@ static void set_links_homedir(const char *homedir) {
 		return;
 	}
 
-	char *firejail_exec;
-	if (asprintf(&firejail_exec, "%s/bin/firejail", PREFIX) == -1)
-		errExit("asprintf");
-
 	// parse ~/.config/firejail/ directory
 	printf("\nConfiguring symlinks in %s based on local firejail config directory\n", arg_bindir);
 
@@ -280,12 +256,10 @@ static void set_links_homedir(const char *homedir) {
 		}
 
 		*ptr = '\0';
-		set_file(exec, firejail_exec);
+		set_file(exec, FIREJAIL_EXEC);
 		free(exec);
 	}
 	closedir(dir);
-
-	free(firejail_exec);
 }
 
 static const char *get_sudo_user(void) {
@@ -449,15 +423,17 @@ int main(int argc, char **argv) {
 	}
 
 	if (arg_guide) {
+		const char *zenity_exec;
+		if (arg_debug)
+			zenity_exec = FZENITY_EXEC;
+		else
+			zenity_exec = ZENITY_EXEC;
+
 		char *cmd;
-if (arg_debug) {
-		if (asprintf(&cmd, "sudo %s/firejail/firejail-welcome.sh /usr/lib/firejail/fzenity %s %s", LIBDIR, SYSCONFDIR, user) == -1)
+		if (asprintf(&cmd, "sudo %s %s %s %s",
+			     FIREJAIL_WELCOME_SH, zenity_exec, SYSCONFDIR, user) == -1)
 			errExit("asprintf");
-}
-else {
-		if (asprintf(&cmd, "sudo %s/firejail/firejail-welcome.sh /usr/bin/zenity %s %s", LIBDIR, SYSCONFDIR, user) == -1)
-			errExit("asprintf");
-}
+
 		int status = system(cmd);
 		if (status == -1) {
 			fprintf(stderr, "Error: cannot run firejail-welcome.sh\n");
@@ -474,8 +450,8 @@ else {
 	// clear all symlinks
 	clean();
 
-	// set new symlinks based on /etc/firejail/firecfg.config
-	set_links_firecfg();
+	// set new symlinks based on firecfg.config
+	set_links_firecfg(FIRECFG_CFGFILE);
 
 	if (getuid() == 0) {
 		// add user to firejail access database - only for root